RESUMO
Schwann cells (SCs) critically maintain the plasticity of the peripheral nervous system. Peripheral nerve injuries and infections stimulate SCs in order to retrieve homeostasis in neural tissues. Previous studies indicate that Mycobacterium leprae (ML) regulates the expression of key factors related to SC identity, suggesting that alterations in cell phenotype may be involved in the pathogenesis of neural damage in leprosy. To better understand whether ML restricts the plasticity of peripheral nerves, the present study sought to determine the expression of Krox-20, Sox-10, c-Jun and p75NTR in SC culture and mice sciatic nerves, both infected by ML Thai-53 strain. Primary SC cultures were stimulated with two different multiplicities of infection (MOI 100:1; MOI 50:1) and assessed after 7 and 14 days. Sciatic nerves of nude mice (NU-Foxn1nu ) infected with ML were evaluated after 6 and 9 months. In vitro results demonstrate downregulation of Krox-20 and Sox-10 along with the increase in p75NTR-immunolabelled cells. Concurrently, sciatic nerves of infected mice showed a significant decrease in Krox-20 and increase in p75NTR. Our results corroborate previous findings on the interference of ML in the expression of factors involved in cell maturation, favouring the maintenance of a non-myelinating phenotype in SCs, with possible implications for the repair of adult peripheral nerves.
Assuntos
Regulação para Baixo , Proteína 2 de Resposta de Crescimento Precoce/biossíntese , Hanseníase/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/metabolismo , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Hanseníase/microbiologia , Hanseníase/patologia , Camundongos Nus , Mycobacterium leprae/isolamento & purificação , Plasticidade Neuronal/fisiologia , Receptores de Fator de Crescimento Neural/metabolismo , Células de Schwann/microbiologia , Células de Schwann/patologia , Nervo Isquiático/microbiologia , Nervo Isquiático/patologia , Técnicas de Cultura de TecidosRESUMO
Schwann cells (SCs) critically maintain the plasticity of the peripheral nervous system. Peripheral nerve injuries and infections stimulate SCs in order to retrieve homeostasis in neural tissues. Previous studies indicate that Mycobacterium leprae (ML) regulates the expression of key factors related to SC identity, suggesting that alterations in cell phenotype may be involved in the pathogenesis of neural damage in leprosy. To better understand whether ML restricts the plasticity of peripheral nerves, the present study sought to determine the expression of Krox20, Sox10, cJun and p75NTR in SC culture and mice sciatic nerves, both infected by ML Thai53 strain. Primary SC cultures were stimulated with two different multiplicities of infection (MOI 100:1; MOI 50:1) and assessed after 7 and 14 days. Sciatic nerves of nude mice (NUFoxn1nu) infected with ML were evaluated after 6 and 9 months. In vitro results demonstrate downregulation of Krox20 and Sox10 along with the increase in p75NTRimmunolabelled cells. Concurrently, sciatic nerves of infected mice showed a significant decrease in Krox20 and increase in p75NTR. Our results corroborate previous findings on the interference of ML in the expression of factors involved in cell maturation, favouring the maintenance of a nonmyelinating phenotype in SCs, with possible implications for the repair of adult peripheral nerves(AU).